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Preliminary Results of Heat Transfer from a Stationary and Rotating Ellipsoidal Spinner

Description: Convective heat-transfer coefficients in dry air were obtained for an ellipsoidal spinner of 30-inch maximum diameter for both stationary and rotating operation over a range of conditions including airspeeds up to 275 miles per hour, rotational speeds up to 1200 rpm, and angles of attack of zero and 40 The results are presented in terms of Nusselt numbers, Reynolds numbers, and convective heat-transfer coefficients. The studies included both uniform heating densities over the spinner and uniform surface temperatures.. In general, the results showed that rotation will increase the convective heat transfer from a spinner, especially in the turbulent-flow regions. Rotation of the spinner at 1200 rpm and at a free-stream velocity of 275 miles per hour increased the Nusselt number parameter in the turbulent-flow region by 32 percent over that obtained with a stationary spinner; whereas in the nose region, where the flow was laminar, an increase of only 18 percent was observed. Transition from laminar to turbulent flow occurred over a large range of Reynolds numbers primarily because of surface roughness of the spinner. Operation at an angle of attack of 40 had only small effects on the local convective heat transfer for the model studied.
Date: August 6, 1953
Creator: von Glahn, U.
Partner: UNT Libraries Government Documents Department

Investigation of equilibrium temperatures and average laminar heat-transfer coefficients for the front half of swept circular cylinders at a Mach number of 6.9

Description: Report presenting the average heat-transfer coefficients and equilibrium temperatures for the front half of an isothermal cylinder with a laminar boundary layer as determined by wind tunnel testing at Mach number 6.9 and a range of Reynolds numbers and sweep angles.
Date: August 18, 1955
Creator: Feller, William V.
Partner: UNT Libraries Government Documents Department

Measurements of heat-transfer and friction coefficients for air flowing in a tube of length-diameter ratio of 15 at high surface temperatures

Description: Report presenting measurements of average heat-transfer and friction coefficients for air flowing through a smooth, electrically heated tube with a bellmouth entrance with a length-to-diameter ratio of 15 and a range of average surface temperatures, Reynolds numbers, exit Mach numbers, and heat fluxes. Results regarding the axial-wall-temperature distribution, heat balance, correlation of heat-transfer coefficients, and correlation of friction coefficient are provided.
Date: July 9, 1953
Creator: Weiland, Walter F. & Lowdermilk, Warren H.
Partner: UNT Libraries Government Documents Department

A Method for Rapid Determination of the Icing Limit of a Body in Terms of the Stream Conditions

Description: The effects of existing frictional heating were analyzed to determine the conditions under which ice formations on aircraft surfaces can be prevented. A method is presented for rapidly determining by means of charts the combination of-Mach number, altitude, and stream temperature which will maintain an ice-free surface in an icing cloud. The method can be applied to both subsonic and supersonic flow. The charts presented are for Mach numbers up to 1.8 and pressure altitudes from sea level to 45,000 feet.
Date: March 1953
Creator: Callaghan, Edmund E. & Serafini, John S.
Partner: UNT Libraries Government Documents Department

Aerodynamic heating of a wing as determined from a free-flight rocket-model test to Mach number 3.64

Description: From Introduction: "The primary purpose of the wing instrumentation was to obtain data for use in design of NACA research missiles; however, it is believed that the wing is representative of typical supersonic designs and that the data will be of general use and interest. Only the wing data are reported herein."
Date: September 11, 1956
Creator: Swanson, Andrew G. & Rumsey, Charles B.
Partner: UNT Libraries Government Documents Department

General Correlation of Temperature Profiles Downstream of a Heated Air Jet Directed at Various Angles to Air Stream

Description: An experimental investigation was conducted to determine the temperature profiles downstream of heated air jets directed at angles of 90 deg, 60 deg, 45 deg, and 30 deg to an air stream. The profiles were determined at two positions downstream of the jet as a function of jet diameter, jet density, jet velocity, free-stream density, free-stream velocity, jet total temperature, orifice flow coefficient, and jet angle. A method is presented which yields a good approximation of the temperature profile in terms of the flow and geometric conditions.
Date: December 1952
Creator: Ruggeri, Robert S.
Partner: UNT Libraries Government Documents Department

Impingement of Cloud Droplets on 36.5-Percent-Thick Joukowski Airfoil at Zero Angle of Attack and Discussion of Use as Cloud Measuring Instrument in Dye-Tracer Technique

Description: The trajectories of droplets i n the air flowing past a 36.5-percent-thick Joukowski airfoil at zero angle of attack were determined. The amount of water i n droplet form impinging on the airfoil, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface were calculated from the trajectories and cover a large range of flight and atmospheric conditions. With the detailed impingement information available, the 36.5-percent-thick Joukowski airfoil can serve the dual purpose of use as the principal element in instruments for making measurements in clouds and of a basic shape for estimating impingement on a thick streamlined body. Methods and examples are presented for illustrating some limitations when the airfoil is used as the principal element in the dye-tracer technique.
Date: September 1, 1957
Creator: Brun, R. J. & Vogt, Dorothea E.
Partner: UNT Libraries Government Documents Department

Heat transfer to bodies in a high-speed rarefied-gas stream

Description: Report presenting measurements of the equilibrium temperature and heat-transfer coefficients for transverse cylinders in a high-speed stream of rarefied gas over a range of Knudsen and Mach numbers. Results regarding the temperature recovery for an insulated body and heat-transfer-test results are provided.
Date: August 1951
Creator: Stalder, Jackson R.; Goodwin, Glen & Creager, Marcus O.
Partner: UNT Libraries Government Documents Department

Heat transfer to 0 degree and 75 degree swept blunt leading edges in free flight at Mach numbers from 1.90 to 3.07

Description: Report presenting an investigation of a rocket-powered model to study the heat transfer to wing leading edges in the vicinity of their juncture with a cylindrical body. Information about heat-transfer measurements, average heat transfer on cylindrical portions of leading edges, and local heat transfer is provided.
Date: March 24, 1958
Creator: O'Neal, Robert L. & Bond, Aleck C.
Partner: UNT Libraries Government Documents Department

Heat transfer to bodies in a high-speed rarified-gas stream

Description: Report presents the results of an investigation to determine the equilibrium temperature and heat-transfer coefficients for transverse cylinders in a high-speed stream of rarefied gas measured over a range of Knudsen numbers (ratio of molecular-mean-free path to cylinder diameter) from 0.025 to 11.8 and for Mach numbers from 2.0 to 3.3. The range of free-stream Reynolds numbers was from 0.28 to 203. The models tested were 0.0010-, 0.0050-, 0.030-, 0.051-, 0.080-, and 0.126-inch -diameter cylinders held normal to the stream.
Date: May 14, 1951
Creator: Stalder, Jackson R.; Goodwin, Glen & Creager, Marcus O.
Partner: UNT Libraries Government Documents Department

Free-flight heat-transfer measurements on two 20 degree-cone-cylinders at Mach numbers from 1.3 to 4.9

Description: Report presenting heat-transfer data obtained in free flight at supersonic Mach numbers up to 4.90 and local Reynolds numbers per foot up to 27.7 million. Two 20 degree-included-angle cone-cylinder models were launched from a carrier airplane at 36,000 feet of altitude. Results regarding primary data and heat-transfer results are provided.
Date: July 18, 1955
Creator: Rabb, Leonard & Simpkinson, Scott H.
Partner: UNT Libraries Government Documents Department

Droplet Impingement and Ingestion by Supersonic Nose Inlet in Subsonic Tunnel Conditions

Description: The amount of water in cloud droplet form ingested by a full-scale supersonic nose inlet with conical centerbody was measured in the NACA Lewis icing tunnel. Local and total water impingement rates on the cowl and centerbody surfaces were also obtained. All measurements were made with a dye-tracer technique. The range of operating and meteorological conditions studied was: angles of attack of 0 deg and 4.2 deg, volume-median droplet diameters from about 11 to 20 microns, and ratios of inlet to free-stream velocity from about 0.4 to 1.8. Although the inlet was designed for supersonic (Mach 2.0) operation of the aircraft, the tunnel measurements were confined to a free-stream velocity of 156 knots (Mach 0.237). The data are extendable to other subsonic speeds and droplet sizes by dimensionless impingement parameters. Impingement and ingestion efficiencies are functions of the ratio of inlet to free-stream velocity as well as droplet size. For the model and range of conditions studied, progressively increasing the inlet velocity ratio from less than to greater than 1.0 increased the centerbody impingement efficiency and shifted the cowl impingement region from the inner- to outer-cowl surfaces, respectively. The ratio of water ingested by the inlet plane to that contained in a free-stream tube of cross section equal to that at the inlet plane also increased with increasing inlet velocity ratio. Theoretically calculated values of inlet water (or droplet) ingestion are in good agreement with experiment for annular inlet configurations.
Date: May 1958
Creator: Gelder, Thomas F.
Partner: UNT Libraries Government Documents Department

A Dye-Tracer Technique for Experimentally Obtaining Impingement Characteristics of Arbitrary Bodies and a Method for Determining Droplet Size Distribution

Description: A dye-tracer technique has been developed whereby the quantity of dyed water collected on a blotter-wrapped body exposed to an air stream containing a dyed-water spray cloud can be colorimetrically determined in order to obtain local collection efficiencies, total collection efficiency, and rearward extent of impingement on the body. In addition, a method has been developed whereby the impingement characteristics obtained experimentally for a body can be related to theoretical impingement data for the same body in order to determine the droplet size distribution of the impinging cloud. Several cylinders, a ribbon, and an aspirating device to measure cloud liquid-water content were used in the studies presented herein for the purpose of evaluating the dye-tracer technique. Although the experimental techniques used in the dye-tracer technique require careful control, the methods presented herein should be applicable for any wind tunnel provided the humidity of the air stream can be maintained near saturation.
Date: March 1955
Creator: von Glahn, Uwe H.; Gelder, Thomas F. & Smyers, William H., Jr.
Partner: UNT Libraries Government Documents Department

Analytical investigation of fully developed laminar flow in tubes with heat transfer with fluid properties variable along the radius

Description: From Introduction: "In the analytical investigation reported herein, which was conducted in the NACA Lewis laboratory, both velocity and temperature distribution are obtained for fully developed laminar flow in tubes of gases and of liquid metals with variable fluid properties."
Date: July 1, 1951
Creator: Deissler, Robert G
Partner: UNT Libraries Government Documents Department

Analytical determination of local surface heat-transfer coefficients for cooled turbine blades from measured metal temperatures

Description: From Summary: "Procedures for applying these analytical methods to experimentally measured blade-metal temperatures are presented. Data are presented for the leading and trailing edge of a symmetrical water-cooled blade to illustrate the validity of the methods for those portions of the blade. In addition to the application to turbine blades, the methods can be applied to any heat-transfer apparatus having a profile that can be approximated by the shape discussed."
Date: April 10, 1950
Creator: Brown, W. Byron & Esgar, Jack B.
Partner: UNT Libraries Government Documents Department

Comparison of Heat Transfer from Airfoil in Natural and Simulated Icing Conditions

Description: An investigation of the heat transfer from an airfoil in clear air and in simulated icing conditions was conducted in the NACA Lewis 6- by 9-foot icing-research tunnel in order to determine the validity of heat-transfer data as obtained in the tunnel. This investiation was made on the same model NACA 65,2-016 airfoil section used in a previous flight study, under similar heating, icing, and operating conditions. The effect of tunnel turbulence, in clear air and in icingwas indicated by the forward movement of transition from laminar to turbulent heat transfer. An analysis of the flight results showed the convective heat transfer in icing to be considerably different from that measured in clear air and. only slightly different from that obtained in the icing-research tunnel during simulated icing.
Date: September 1, 1951
Creator: Gelder, Thomas F. & Lewis, James P.
Partner: UNT Libraries Government Documents Department

Analysis of fully developed turbulent heat transfer at low Peclet numbers in smooth tubes with application to liquid metals

Description: From Introduction: "Analyses of heat transfer for liquid metals flowing turbulently in smooth tubes (low Pradtl numbers) are given in reference 1 and 2. The predicted heat-transfer coefficients from these analyses are considerably higher than those determined in the experimental heat-transfer investigations for mercury and lead bismuth given in references 2 to 4. If the analytical and experimental results for flow of gases are compared at low Peclet numbers, they are also found to be in disagreement (references 5 and 6)."
Date: August 11, 1952
Creator: Deissler, Robert G
Partner: UNT Libraries Government Documents Department

Analysis of fully developed turbulent heat transfer and flow in an annulus with various eccentricities

Description: From Introduction: "Most of the existing analyses for turbulent flow and heat transfer in passages have been confined to circular tubes or parallel plates (refs. 1 to 5). In reference 6, temperature distributions for rectangular and triangular ducts were calculated by using experimental velocity distributions and average heat-transfer coefficients. Some work on the calculation of the velocity and shear-stress distributions in corners is reported in reference 7."
Date: May 1955
Creator: Deissler, Robert G & Taylor, Maynard F
Partner: UNT Libraries Government Documents Department

Analysis of laminar forced-convection heat transfer in entrance region of flat rectangular ducts

Description: From Introduction: "Beyond the position where the boundary layer treatment can no longer be used, curves have been faired to connect the Nusselt number results of the present analysis with those of reference 3, in which a parabolic velocity profile is assumed throughout the entire duct length. So that a comparison could be made with the results of reference 3, the boundary layer analysis was used to study the development of the temperature profile associated with a parabolic velocity profile throughout."
Date: January 1955
Creator: Sparrow, E M
Partner: UNT Libraries Government Documents Department

An analysis of laminar free-convection flow and heat transfer about a flat plate parallel to the direction of the generating body force

Description: From Introduction: "The problem of free-convection flow as produced by a body force about a flat plate in the direction of the body force was studied at the NACA Lewis laboratory and is treated in a formal and more general manner herein. The method used is somewhat similar to that used in reference 4 wherein consideration was given to the free-convection flow at high Grashof numbers in a horizontal cylinder which had a variable surface-temperature distribution. In addition, the numerical solutions of references 2 and 3 are herein extended to cover a more complete range of variables."
Date: February 1, 1952
Creator: Ostrach, Simon
Partner: UNT Libraries Government Documents Department

An analysis of laminar free-convection flow and heat transfer about a flat plate paralled to the direction of the generating body force

Description: From Introduction: "Although the final equations obtained by this method are the same as those of Schmidt and Beckmann, this more general approach not only clearly demonstrates the significance of all the important parameters and assumptions and hence leads to a better understanding of this type of flow but also indicates the quantitative limitations of the theory. In addition, the numerical solutions of references 2 and 3 are herein extended to cover a more complete range of parameters."
Date: 1953~
Creator: Ostrach, Simon
Partner: UNT Libraries Government Documents Department

Experiments on mixed-free-and-forced-convective heat transfer connected with turbulent flow through a short tube

Description: Report presenting experiments conducted to obtain information on heat transfer in turbulent, mixed-free- and -forced-convection flow. The investigation revealed that the total flow regime as characterized by its Reynolds and Grashof numbers can be subdivided into a forced-flow regime, a free-flow regime, and a mixed-free- and -force-convection regime.
Date: July 1953
Creator: Eckert, E. R. G.; Diaguila, Anthony J. & Curren, Arthur N.
Partner: UNT Libraries Government Documents Department